Although 3D laser scanners are improving in quality, the point cloud scan files obtained from 3D scanners do not accurately represent the true dimensions of the actual object due to various types of noise such as statistical noise and false scatter points.
Laser scanner technicians have developed methods using registration markers in various forms or shapes known within the software of the laser scanner to aid in accurate measurement with little success. Even with the use of these objects, such as a sphere designed to be fully recognized by the scanner, the point cloud is not accurately represented and, instead, is distorted.
Aside from attempts to fine tune the laser scanners themselves, when tools designed to measure between scan points are utilized, they also fail to show the full expected field of view and oftentimes deviate by a significant amount.
It is recognized that some 3D images need smoothing in order to take accurate measurements of an object; however, these smoothing techniques distort and/or diminish the density of the original scan data. Other attempts do not rid the image of statistical noise to a high enough degree to be useful for small measurements. Another shortfall of typical 3D scans is the amount of scatter points and surface roughness included in scan files which mask the true shape of the object being measured. For example, if minute measurements are needed to monitor the deformation of an object to determine whether the structural integrity has been compromised for engineering purposes, this cannot be done to a high degree of certainty with various forms of noise present and, currently, the software and techniques for tuning the laser scanners do not provide adequate images.